Extracting minerals from space rocks sounds like science fiction, no matter how you parse it. Still, some of the world’s richest businessmen, including Google (NASDAQ:GOOG) executives Larry Page and Eric Schmidt and filmmaker James Cameron, are backing the idea.

A new company called Planetary Resources, founded by Peter Diamandis and Eric Anderson, will spearhead the mining plan, according to the Associated Press. The company’s co-founders pioneered the idea of selling low-orbital plane rides to tourists.

The plan’s first phase will see the launch of small orbital telescopes to locate mineral-rich asteroids — chunks of rock left over from the solar system’s formation. Roughly 1,500 asteroids swing close to the Earth during their orbits around the sun. Planetary Resources expects about 10% of these to have frozen water and minerals worth mining.

The company hopes to send mining robots to passing asteroids and dig into their surfaces in search of precious minerals. Once extracted, the minerals would be stored in Earth orbit for use by other space-based operations.

Finding water in space is crucial. Water is too expensive to transport from Earth, so the robots must find it on asteroids, likely as ice. Once found, water can be converted into fuel.

Space experts are skeptical of the venture, pointing out that developing such mining machines and getting them anywhere near an asteroid will cost billions of dollars. NASA’s next Mars rover, for example, will cost at least $2.5 billion.

However, the backers of the asteroid mining operation contend that the technology is within reach. With the backing of Google billionaires and a leading Hollywood filmmaker, they think they have the resources to shoot for the stars.

Or asteroids, at least.